Fenbendazole in Pheasants Human Food Safety (Tissue Residue) Study Study Number 2010-280-HFS ADR Number 280 PROJECT SUMMARY Fenbendazole (Safeguard(R)) is a highly-effective benzimidazole-class anthelmintic that is commonly used for the control of nematodes, tapeworms and trematodes that infect several domestic animal species in the United States. Fenbendazole has been reported to be effective against parasites that commonly infect game birds that are raised on commercial propagation farms;however, it is not currently approved for game birds in the United States. Ring-necked pheasants raised on propagation farms can be routinely infected with Heterakis gallinae (cecal worm), Syngamus trachea (gapeworm) and other parasitic worms that are susceptible to fenbendazole treatment. Depending on the severity of the infection, morbidity and mortality can be quite high. The purpose of this study is to determine the tissue residues of fenbendazole in ring-necked pheasants fed a diet containing approximately 100 ppm fenbendazole. Birds will be reared to 11 to 12 weeks of age on non-medicated commercial game bird diets. Group 1 (control birds) will continue to be fed the non-medicated (basal) diet. Birds in Group 2 will be fed 100 ppm (90.4g/ton) fenbendazole added to the basal diet from days 0 to 7. On Day 7 the fenbendazole-containing feed will be removed and replaced with the basal diet. A designated number of birds from both groups will be humanely euthanized at 6-8, 12, 24 and 48 hours following fenbendazole withdrawal. Liver and muscle tissues will be removed from the birds at each time point according to SOP, quickly frozen and stored at -80 C until tissues have been collected from all study animals. The tissues will be shipped by overnight express to the analytical laboratory at the University of California, Davis. Tissues will be analyzed for fenbendazole residues using the established regulatory method. The data obtained from this study will be utilized to establish a withdrawal time for fenbendazole in pheasants. This study will be considered pivotal.